The invention relates generally to transmission lines and more particularly to high voltage pulse shaping.
The Nova Laser at LLNL is a high power laser having multiple amplifier chains. A master oscillator provides optical pulses with selectable duration for input to the amplifier chains. To generate these optical pulses light from a long pulse oscillator is passed through a Pockels cell gate driven by a shaped high voltage pulse. To create a properly shaped optical pulse a properly shaped high voltage pulse is required. Ideally, the pulse from the laser amplifier should be uniform, i.e., squarewave. However, gain saturation in the amplifier changes the pulse shape so that a squarewave input pulse will not produce a squarewave output pulse. Gain saturation causes reduction in gain over the duration of the pulse and thus temporal distortion. Therefore, the input pulse must be shaped to compensate for the distortion produced in the amplifier so that the output pulse has the desired shape. Conventional electronic circuits do not provide the required pulse shaping capability.
Accordingly, it is an object of the invention to provide method and apparatus for forming high voltage pulses.
It is another object of the invention to produce high voltage pulses of a selected shape.
It is a further object of the invention to provide method and apparatus by which the pulse shape may be easily changed.
It is also an object of the invention to produce shaped high voltage pulses to drive a Pockels cell gate to generate optical pulses for a laser amplifier system.